import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class TcpEchoServer {
    private ServerSocket  serverSocket = null;
    public TcpEchoServer(int port) throws IOException {
        serverSocket = new ServerSocket(port);
    }
    public void start() throws IOException {
        System.out.println("服务器启动！");
        while(true){
            Socket cilentSocket = serverSocket.accept();
            ExecutorService service = Executors.newCachedThreadPool();
            service.submit(new Runnable() {
                @Override
                public void run() {
                    processConnection(cilentSocket);
                }
            });
        }
    }
    public void processConnection(Socket cilentSocket) {
        System.out.printf("[%s:%d]客户端上线\n",cilentSocket.getInetAddress(),cilentSocket.getPort());
        try(InputStream inputStream = cilentSocket.getInputStream();
            OutputStream outputStream = cilentSocket.getOutputStream()){
            while(true){
                Scanner scanner = new Scanner(inputStream);
                if(!scanner.hasNext()){
                    System.out.printf("[%s:%d]客户端下线\n",cilentSocket.getInetAddress(),
                                                          cilentSocket.getPort());
                    break;
                }
                String request = scanner.next();
                String response = process(request);
                PrintWriter printWriter = new PrintWriter(outputStream);
                printWriter.println(response);
                printWriter.flush();
                System.out.printf("[%s:%d] rep=%s,resp=%s\n",cilentSocket.getInetAddress(),
                                                             cilentSocket.getPort(),request,response
                                                             );
            }
        } catch (IOException e) {
            throw new RuntimeException(e);
        } finally {
            try{
                cilentSocket.close();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
    }
    public String process(String request){
        return  request;
    }

    public static void main(String[] args) throws IOException {
        TcpEchoServer server = new TcpEchoServer(9090);
        server.start();
    }
}